Multi-tyrosine kinase inhibitors derivatives and methods of use

ABSTRACT

The present invention is directed to multi-tyrosine kinase inhibitor compounds. The present invention is further directed to compositions comprising those compounds. Finally, the present invention is directed to methods of treating eye conditions including, but not limited to, diabetic background retinopathy, diabetic macular edema, diabetic proliferative retinopathy, diabetic macular edema with proliferative retinopathy, proliferative fibrovascular disease, diabetic macular edema with proliferative fibrovascular disease, retinopathy of prematurity, dry macular degeneration, dry macular degeneration with drusen and wet macular degeneration, using compounds and compositions of the invention.

BACKGROUND OF THE INVENTION

Many intraocular diseases, such as proliferative retinopathies, occurdue to neovascularization and/or leakage, which are caused in part byelevated vascular endothelial growth factor (“VEGF”) levels. Thesediseases include, but are not limited to, diabetic macular edema,diabetic proliferative retinopathy, retinopathy of prematurity, diabeticvitreal traction, wet macular degeneration and attendantneovascularization through Bruch's membrane between the choroid andretina, branch vein occlusion, complete retinal vein occlusion,maculopathies such as Best's disease, ischemic intraocular insultresulting in neovascular rubeotic (iris, anterior chamber angleneovascularization) glaucoma, and on or within the cornea coincidingwith herpes simplex keratitis or a graft rejection.

Diabetic macular edema is the most common cause of vision loss amongdiabetics. Due to the increase in diabetes (both type I and type II) indeveloped countries such as the United States, diabetic macular edema isalso the most common cause of vision loss among working-aged adults.Diabetic macular edema results when insulin resistance causes thevascular lining of blood vessels to thicken, resulting in capillary dropout, microaneurysms, ischemia, and leakage in the retina. The resultinghypoxia triggers an increase in the production of VEGFs, which in turnis a potent inducer of vascular permeability (leakage) and eventuallyresults in the production of new blood vessels. These leaking bloodvessels leak fluid into the macula causing the macula to swell resultingin vision loss, as well as eventually causing new blood vessel growthalong the retina and into the vitreous causing proliferative retinopathywith high morbidity from bleeding and retinal detachment from resultingvitreous traction and scarring.

Macular degeneration is a disease of the eye that results in minor tosevere impairment of the subject's sharp central vision, which isnecessary for activities such as reading and driving. Age-relatedmacular degeneration (“AMD”) afflicts an estimated 30 to 50 millionpeople worldwide and is the leading cause of severe vision loss inWestern societies. AMD disrupts the photoreceptors of the macula in oneof two ways: (1) deposits of extracellular debris between Bruch'smembrane and the retinal pigment epithelium known as “dry” maculardegeneration and (2) breaks in Bruch's membrane that allow angiogenicblood vessels from the choroid to penetrate the retinal pigmentepithelium known as “wet” macular degeneration. Dry AMD progressesslowly and is responsible for about 90% of AMD worldwide. Wet AMD can besudden, severe and irreversible due to bleeding and scarring of themacular region including the fovea. Although wet AMD accounts for only10% of AMD worldwide it is responsible for 90% of AMD-associatedblindness.

VEGFR pathways are the main pharmaceutical targets of angiogenicsuppression. Anti-angiogenesis drugs that target VEGFR pathways and areused in the eye include bevacizumab (Avastin®; Avastin is a registeredtrademark of Genentech, Inc.), ranibizumab (Lucentis®; Lucentis is aregistered trademark of Genentech, Inc.) and recombinant fusion proteinssuch as aflibercept (Eylea®; Eylea is a registered trademark ofRegeneron Pharmaceuticals, Inc.). These anti-VEGF protein drugs, whichare too large to formulate for topical applications, require aninjection monthly or several times per year to limit further visionloss. Currently, the morbidity, inconvenience, and expense of theseinjectables limit treatment to only severe pathologic states, becausethey are too invasive for routine prophylaxis prior to onset ofsignificant pathology. For example, prophylactic administration wouldbenefit wet macular degeneration such as in the presence of confluent orotherwise near confluent macular drusen of dry macular degeneration (aknown predisposing risk factor for retinal pigment epithelium layercracks and choroidal neovascularization). In another example,prophylactic administration would benefit the presence in diabetics ofbackground diabetic retinopathy at various points of disease progressionprior to the development of diabetic macular edema (e.g., macular orparamacular exudate, high density of dot blot hemorrhages) and mostparticularly prior to the development of proliferative retinopathy withor without macular edema such as in the presence of severe capillarydrop out, and still more particularly in the presence of proliferativeretinopathy prior to the development of fibrovascular retinopathy andattendant retinal traction and epiretinal formation. The inability touse these drugs as a prophylactic treatment modality limits theireffectiveness in preventing early vision loss, but rather restricts themlargely to treating only existing visual loss that can be extensive evenat initial diagnosis.

Once in the vitreous humor these anti-VEGF proteins have a half-life ofabout 9 days, a high IC50 VEGFR inhibition value, fast release rate dueto their hydrophilic nature and immediate dispersion within the vitreoustowards tissue receptors, and interact with only one angiogenicreceptor, VEGF. All of these qualities result in the need for a varietyof formulation techniques required to attempt to enhance the residencetime of the drug within the vitreous humor to achieve the more prolongedeffect that would add safety and efficacy from a single injection. Theseformulation techniques include attempts at high concentrations, highvolumes of bolus injection, emulsions, encapsulation techniques, andother sustained-release compositions; though their highly hydrophilicnature, relatively high concentrations required for efficacy (IC50 about19 nM for Lucentis®), and limitations imposed on protein stabilitywithin solution restrict their potential for additional sustainedduration via direct injection. As a result, although these drugs reducedisease morbidity they still add serious injection related morbidityexacerbated by the high frequency of injections required per year, wheresuch injection induced morbidity includes but is not limited toendophthalmitis (intraocular severe infection often with complete visionloss), cataract, glaucoma, and vitreous traction that for many patientscan be devastating.

To achieve 30-day duration of effect requires the maximum injectablevolume tolerable by the human eye, about 50 uL, at about 0.50%. Suchhigh bolus volumes frequently result in high intraocular pressure up to49 mm Hg. Additionally, attempts to overcome these formulation andadministration challenges can be problematic limited by propertiesintrinsic to these protein anti-VEGF molecules. For example, thepathology of the disease to be treated exposes these active agents to avariety of noxious stimuli including a more ischemic and acidicenvironment, which can cause these proteins to denature and degrade morerapidly and therefore compromise their potency when delivered via asustained-release device. Particularly, the least invasive class ofinjectable sustained release implants, such as biodegradable implantssuch as Ozurdex®/Pozurdex® (Ozurdex is a registered trademark ofAllergan, Inc.) releases glycolic and lactic acid that limit theusefulness of proteins for such devices due to rapid low pHdenaturation. Finally, the efficacy of this class of drugs is limited bysubstantial tachyphylaxis and resistance that develops over time due totheir inhibition of only VEGF's and not additional angiogenic receptors.

Additional tyrosine kinase receptors (“ancillary receptors”) involved inangiogenesis in addition to VEGFR have also been discovered and found toconfer additional antiangiogenic benefit above that of VEGFR onlyinhibition as seen with protein anti-VEGF drugs such as Lucentis®,Avastin®, and Eylea®. The suppression of these ancillary receptors isknown to enhance the anti-angiogenic effect of VEGFR pathwaysuppression. These ancillary receptors include platelet-derived growthfactor receptors (“PDGFR”) a and (3, fibroblast-derived growth factorreceptors (“FDGFR”) 1-4, c-KIT, and TIE 1-3, and particularly c-MET.Upregulation of c-MET is known to occur following anti-VEGF treatmentand result in tachyphylaxis/resistance to such drugs with expression ofangiogenic behavior resulting. Suppression of one or more of theseancillary receptors in conjunction with suppression of a VEGFR,including but not limited to c-MET, is common in the art and is known asmulti-receptor tyrosine kinase inhibition. Multi-receptor tyrosinekinase inhibition for treatment of angiogenesis is known to decrease theincidence and severity of tachyphylaxis or resistance in response tosuppression of a VEGFR alone. One such multi-tyrosine kinase inhibitor(“MTKI”) is cabozantinib (Cometriq®; Cometriq is a registered trademarkof Exelixis, Inc.). Cabozantinib inhibits VEGFR2 at nearly 1/500th(0.214%) of Avastin® (bevacizumab, Genentech®/Roche®), with an IC50 ofabout 35 picomolar (“pM”) vs 1400 pM respectively in in vitro angiogenicassays for inhibition of human umbilical vascular endothelial cells(“HUVEC”). Cabozantinib also inhibits to various degrees otherangiogenic receptors including PDGFR, FLT, TIE-2, and c-MET and wasapproved by the U.S. FDA for the treatment of medullary thyroid cancer.

Pharmaceutical use of tyrosine kinase inhibitors (“TKIs”) and morespecifically MTKI's for intraocular use is complicated by their highpermeability through cell membranes, their impermeability in solutionand their high degrees of lipophilicity. These complications limitMTKI's ability to be formulated beyond their most common use for oralcancer treatment. Further, MTKI's such as cabozantinib when administeredorally may lead to perforation of the colon. Intravenous administrationis also problematic due to the short half-life of MTKI's such ascabozantinib.

Intravitreal injection is complicated by the sensitivity of theintraocular structures, particularly the optic nerve and nerve fiberlayer of the retina to even low concentrations of solvents thatsolubilize or help stabilize other formulations such as emulsions.Though the moderate to high lipophilicity typical of this class mayconfer some resistance to vitreous degradation and prolong duration onceinjected the small molecular weight of on average about 500 daltons vs.for example Lucentis® at 40,000 daltons is inversely proportional todrug retention and hence duration. All of the molecules used in VEGFinhibition, including multi-receptor tyrosine kinase inhibition havechemotherapeutic application and have a risk of severe systemic sideeffects with high systemic absorption. This risk remains forintravitreal injection due to the high cell permeability of this classof drugs. Pazopantinib has undergone up to 10 Phase II efficacy trialsbetween 2008 and 2014 for topical ant-VEGF treatment. However, none ofthe efficacy trials for Pazopantinib are for invitreal administration.The lack of intravitreal administration efficacy trials for pazopantinibis most likely due to its rapid intravitreal clearance estimated to bewithin hours for its molecular weight.

Thus, while there is a need in the art for a long-lasting effectiveinhibitor of angiogenesis and vascular leakage within the eye,particularly a safe and prolonged intravitreal, TKI's or MTKI's thathave sufficient duration of activity and a reduced incidence of systemicside effects have to date not been discovered. Those MTKI's that havebeen tested have not met these ideals and have not been successful forthis purpose.

SUMMARY OF THE INVENTION

The present invention is directed to a compound comprising:

a multi-tyrosine kinase inhibitor (MTKI), preferably the MTKI has anIC50 of 10 nanomolar (“nM”) or less for one or more proteins selectedfrom the group consisting of VEGFR2, c-MET PDGF, FGF, FLT, c-KIT, RONand TIE, more preferably 5 nM or less for VEGFR2, even more preferably0.5 nM or less and most preferably 0.05 nM or less, yet more preferablythe MTKI also has an IC50 for c-Met of 10 nM or less, more preferably 5nM or less, most preferably 3 nM or less and yet even more preferablythe MTKI is selected from the group consisting of cabozantinib,axitinib, cediranib, ponatinib, foretinib, MGCD-265, motesanib,regorafenib, tivozanib and sunitinib, most preferably cabozantinib orforetinib; and a moiety comprising an optionally substituted C2 to C25alkyl group optionally bound to a peptide or a protein, wherein themoiety modifies the MTKI at one or more nitrogens and or the moietyreplaces one or more carbonyl or methoxy groups of the MTKI and whereinif the MTKI has n carbonyl and methoxy groups and n is greater than 1,then n−1 of the carbonyl or methoxy groups are each individually andoptionally absent or optionally replaced by hydrogen, oxygen, carbon,potassium, sulfur, phosphorus, nitrogen, a carbonyl, a sulfhydryl, aphosphatyl, an amide, an amine, a quaternary amine, a phosphate, aphosphonate, a sulfate, a sulfonate, a carboxylate and a urethane.

In a preferred embodiment, the peptide is 10 amino acids or less.

In another preferred embodiment, the moiety comprises albumin.

The C2 to C25 alkyl group may be acyclic or heterocyclic and may besubstituted at one or more hydrogens and or one or more carbons withpolar groups selected from the group consisting of a carbonyl, asulfhydryl, a phosphate, a phosphatyl, a phosphonate, an amide, anamine, a quaternary amine, sulfate, a sulfonate and a carboxylate.Alkyls may be individually substituted at any carbon in the chain bynitrogen or oxygen.

In another preferred embodiment, the moiety provides binding to vitreousproteins or plasma proteins, preferably albumin.

In another preferred embodiment, the moiety renders the compoundamphiphilic.

In another preferred embodiment the carbonyl, the sulfhydryl, thephosphate, the phosphatyl, the phosphonate, the amide, the amine, thequaternary amine, the sulfate, the sulfonate or the carboxylate areindividually substituted with a fatty acid or a second alkyl, preferablypalmitate.

In another embodiment, the moiety is attached to the MTKI via a linkerselected from the group consisting of a bond, an optionally substitutedalkyl, an optionally substituted alkyl-O—, a urethane, and estersthereof.

In another preferred embodiment, the polar moiety provides binding tovitreous proteins or plasma proteins, preferably albumin.

In a preferred embodiment, the present invention is directed to acompound of formula (I)

wherein R¹, R², R³, R⁴ and R⁵ are each individually selected fromabsent, hydrogen, oxygen, carbon, potassium, sulfur, phosphorus,nitrogen, —O—CH₃, a carbonyl, a sulfhydryl, a phosphatyl, an amide, anamine, a quaternary amine, a phosphate, a phosphonate, a sulfate, asulfonate, a carboxylate, a urethane and an optionally substituted C2 toC25 alkyl group optionally bound to a peptide or a protein and at leastone of R¹, R², R³, R⁴ and R⁵ is not absent, hydrogen, oxygen, carbon,potassium, sulfur, phosphorus, nitrogen, —O—CH₃, a carbonyl, asulfhydryl, a phosphatyl, an amide, an amine, a quaternary amine, aphosphate, a phosphonate, a sulfate, a sulfonate, a carboxylate or aurethane.

In a more preferred embodiment the optionally substituted C2 to C25alkyl group is substituted at a hydrogen or a carbon with one or moresubstituents selected from the group consisting of an optionallysubstituted carbonyl, sulfhydryl, phosphate, phosphatyl, phosphonate,amide, amine, quaternary amine, sulfate, sulfonate and carboxylate.

In another more preferred embodiment, the one or more substituents areoptionally substituted with a fatty acid or a second alkyl, preferablypalmitate.

In another more preferred embodiment, the present invention is directedto a compound of formula (I) wherein R¹ is

and wherein R², R³, R⁴ and R⁵ are each H and wherein X is a peptide, aprotein or absent.

In another more preferred embodiment, the present invention is directedto a compound of formula (I) wherein R¹ is

and wherein R² is O and wherein R³, R⁴ and R⁵ are each H and wherein Xis a peptide, a protein or absent.

In another more preferred embodiment, the present invention is directedto a compound of formula (I) wherein R¹ and R² are each individuallyselected from H, O, —O—CH₃, —COOH, and an optionally substituted C2 toC25 alkyl group bound to a peptide or a protein and wherein R³, R⁴ andR⁵ are each H and wherein at least one of R¹ and R² is not H.

In another embodiment, the present invention is directed to acomposition comprising a compound of the present invention and one ormore pharmaceutically acceptable excipients.

In another embodiment, the present invention is directed to a method oftreating a condition of the eye, preferably selected from diabeticbackground retinopathy, diabetic macular edema, diabetic proliferativeretinopathy, diabetic macular edema with proliferative retinopathy,neovascular glaucoma, retinopathy of prematurity, proliferativefibrovascular disease, diabetic macular edema with proliferativefibrovascular disease, retinopathy of prematurity, dry maculardegeneration, any retinopathies with vascular leakage such as Coat'sdisease or Bescet's disease, dry macular degeneration with drusen andwet macular degeneration, comprising administering via intravitrealinjection or topical application of a therapeutically effective amountof a compound of the invention to a subject in need thereof.

In a preferred embodiment administration via intravitreal injection ofcompounds of the present invention occurs no more than once every 3months, more preferably once every 6 months and even more preferablyonce every 9 months.

In another embodiment, the present invention is directed to a method oftreating diabetic macular edema comprising administering viaintravitreal injection or topical application of a therapeuticallyeffective amount of a compound of the invention to a subject in needthereof, wherein proliferative retinopathy is prevented.

In another embodiment, the present invention is directed to a method oftreating diabetic macular edema with proliferative retinopathycomprising administering via intravitreal injection or topicalapplication of a therapeutically effective amount of a compound of theinvention to a subject in need thereof, wherein proliferativeretinopathy is suppressed.

In another embodiment, the present invention is directed to a method oftreating diabetic macular edema comprising administering viaintravitreal injection or topical application of a therapeuticallyeffective amount of a compound of the invention to a subject in needthereof, wherein fibrovascular proliferative disease is prevented.

In another embodiment, the present invention is directed to a method oftreating diabetic macular edema with fibrovascular proliferative diseasecomprising administering via intravitreal injection or topicalapplication of a therapeutically effective amount of a compound of theinvention to a subject in need thereof, wherein fibrovascularproliferative disease is suppressed.

In another embodiment, the present invention is directed to a method oftreating dry macular degeneration or dry macular degeneration withdrusen comprising administering via intravitreal injection or topicalapplication of a therapeutically effective amount of a compound of theinvention to a subject in need thereof, wherein wet macular degenerationis suppressed or prevented.

In another embodiment, the polar moiety provides binding to vitreousproteins or plasma proteins, preferably albumin, such that treating acondition of the eye requires intravitreal injection or topicalapplication of a therapeutically effective amount of a compound of theinvention to a subject in need thereof, wherein the administrationoccurs no more than once every 3 months, preferably, no more than onceevery 6 months and more preferably no more than once every 9 months.

DETAILED DESCRIPTION OF THE INVENTION

Intravitreal administration of the MTKI derivatives of the presentinvention results in a controlled-release of MTKI in the form of adelayed-release or a slow-release (i.e. a sustained-release) resultingin reduced system toxicity and prolonged treatment of eye condition peradministration. This controlled-release is achieved by the use of MTKIderivatives containing C2 to C25 alkyl group optionally bound to apeptide or a protein moiety, which bind to endogenous vitreous proteinsor plasma proteins, particularly albumin. Once the bound albumin breaksdown the moiety then binds to a new endogenous whole albumin proteinproviding longer half-life than an MTKI bound directly to albumin, whichbecomes active as soon as the bound albumin breaks down. To treatconditions of the retina, the MTKI derivatives of the present inventionbound to albumin are endocytosed by cells of the retinal pigmentepithelium layer. This relatively slow degree of hydrolysis andendocytosis results in a very low concentration of MTKI derivativereleased into the retina over a long period of time.

Further, the long half-life of the MTKI derivatives of the presentinvention are beneficial for use as an intravenous injection leading tolonger plasma duration. The MTKI derivatives of the present inventionmay also be administered via the oral route. MTKI derivatives of thepresent invention may lead to higher patient tolerance than MTKI's dueto the ability to be absorbed through the intestinal wall withoutcausing major disturbances such as perforation of the colon.

Definitions

As used in the specification and the appended claims, the singular forms“a,” “an” and “the” include plural referents unless the context clearlydictates otherwise. Thus, for example, reference to “a functionalgroup,” “an alkyl,” or “a residue” includes mixtures of two or more suchfunctional groups, alkyls, or residues, and the like.

As used herein, the term “composition” is intended to encompass aproduct comprising the specified ingredients in the specified amounts,as well as any product which results, directly or indirectly, from acombination of the specified ingredients in the specified amounts.

The terms “treating” and “treatment” refer to reversing, alleviating,inhibiting, preventing, suppressing or slowing the progress of thedisease, disorder, or condition to which such terms apply, or one ormore symptoms of such disease, disorder, or condition.

As used herein, the term “effective amount” refers to an amountsufficient to affect a desired biological effect, such as a beneficialresult, including, without limitation, prevention, diminution,amelioration or elimination of signs or symptoms of a disease ordisorder. Thus, the total amount of each active component of thepharmaceutical composition or method is sufficient to show a meaningfulsubject benefit. Thus, an “effective amount” will depend upon thecontext in which it is being administered. An effective amount may beadministered in one or more prophylactic or therapeutic administrations.

As used herein, the term “pharmaceutically acceptable” describes amaterial that is not biologically or otherwise undesirable, i.e.,without causing an unacceptable level of undesirable biological effectsor interacting in a deleterious manner.

As used herein, the terms “prolonged release” “slow release” and“sustained release” describe release of the active form of a drug over aperiod of time that starts immediately upon administration of the drugand ends sometime after the administration of the drug.

As used herein, the term “delayed release” describes the release of theactive form of a drug that starts after the administration of the drug.

As used herein, the term “controlled release” describes the release ofthe active form of a drug after the administration of the drug.

As used herein the IC50 measurements for VEGFR2 and c-MET were based onmeasurements taken in human umbilical vein endothelial cells.

As used herein, the term “substituted” is contemplated to include allpermissible substituents of organic compounds. In a broad embodiment,the permissible substituents include acyclic and cyclic, branched andunbranched, carbocyclic and heterocyclic, and aromatic and nonaromaticsubstituents of organic compounds. Illustrative substituents include,for example, those described below. The permissible substituents can beone or more and the same or different for appropriate organic compounds.For purposes of this disclosure, the heteroatoms, such as nitrogen, canhave hydrogen substituents and/or any permissible substituents oforganic compounds described herein which satisfy the valences of theheteroatoms. This disclosure is not intended to be limited in any mannerby the permissible substituents of organic compounds. Also, the terms“substitution” or “substituted with” include the implicit proviso thatsuch substitution is in accordance with permitted valence of thesubstituted atom and the substituent, and that the substitution resultsin a stable compound, e.g., a compound that does not spontaneouslyundergo transformation such as by rearrangement, cyclization,elimination, etc. It is also contemplated that, in certain embodiments,unless expressly indicated to the contrary, individual substituents canbe further optionally substituted (i.e., further substituted orunsubstituted).

The term “alkyl” as used herein is a branched or straight-chain alkylconsisting of a saturated hydrocarbon group of 1 to 25 carbon atoms(C₁-C₂₅) unless otherwise stated, such as methyl, ethyl, n-propyl,isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl,s-pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl,tetradecyl, hexadecyl, eicosyl, tetracosyl, and the like. The alkylgroup can be cyclic or acyclic. The alkyl group can be branched orstraight-chained. The alkyl group can also be substituted orunsubstituted. For example, the alkyl group can be substituted athydrogen or carbon atoms with one or more groups including, but notlimited to, alkyl, cycloalkyl, alkoxy, amino, ether, halide, hydroxy,nitro, silyl, sulfo-oxo, thiol, a phosphate, a sulfate a carbonyl, asulfhydryl, a phosphatyl, a phosphonate, an amide, an amine, aquaternary amine, a sulfonate or a carboxylate. Carbon atoms canadditionally be substituted with oxygen or nitrogen atoms.

The term “carbonyl” as used herein refers to a compound of the structure

The term “sulfhydryl” as used herein refers to a compound of thestructure

The term “amide” as used herein refers to a compound of the structure

The term “amine” as used herein refers to a compound of the structure

wherein X¹ and X² are each independently an H or an optionallysubstituted alkyl and wherein at least one of X¹ and X² are not H.

The term “quaternary amine” as used herein refers to a compound of thestructure

wherein X′, X² and X³ are each independently an H or an optionallysubstituted alkyl and wherein at least one X′, X² and X³ are not H.

The term “phosphate” as used herein refers to a compound of thestructure

The term “phosphonate” as used herein refers to a compound of thestructure

The term “sulfate” as used herein refers to a compound of the structure

The term “sulfonate” as used herein refers to a compound of thestructure

The term “carboxylate” as used herein refers to a compound of thestructure

The term “urethane” as used herein refers to a compound of the structure

wherein X¹, is an H or an optionally substituted alkyl, wherein theoptionally substituted alkyl is optionally substituted with

or

The term “fatty acid” as used herein refers to a compound of thefollowing structure

wherein X is a saturated or unsaturated aliphatic chain containing from2 to 28 carbons.

“R¹,” “R²” “R³”, “R⁴” and “R⁵” as used herein, each individually absentor refer to a compound selected from hydrogen, oxygen, carbon,potassium, sulfur, phosphorus, nitrogen, —O—C, a carbonyl, a sulfhydryl,a phosphatyl, an amide, an amine, a quaternary amine, a phosphate, aphosphonate, a sulfate, a sulfonate, a carboxylate, a urethane and anoptionally substituted C2 to C25 alkyl group optionally bound to apeptide or a protein wherein the carbonyl, sulfhydryl, phosphatyl,amide, amine, quaternary amine, phosphate, phosphonate, sulfate,sulfonate, carboxylate, urethane are optionally bound to a second alkylor a fatty acid.

As used herein the term “peptide” refers to a chain of 2 to 49 aminoacids bound together via peptide bonds.

As used herein the term “protein” refers to a chain of at least 50 aminoacids bound together via peptide bonds and oligomers and polymersthereof.

Compounds described herein can contain one or more double bonds and,thus, potentially give rise to cis/trans (E/Z) isomers, as well as otherconformational isomers. Unless stated to the contrary, the inventionincludes all such possible isomers, as well as mixtures of such isomers.

Unless stated to the contrary, a formula with chemical bonds shown onlyas solid lines and not as wedges or dashed lines contemplates eachpossible isomer, e.g., each enantiomer and diastereomer, and a mixtureof isomers, such as a racemic or scalemic mixture. Compounds describedherein can contain one or more asymmetric centers and, thus, potentiallygive rise to diastereomers and optical isomers. Unless stated to thecontrary, the present invention includes all such possible diastereomersas well as their racemic mixtures, their substantially pure resolvedenantiomers, all possible geometric isomers, and pharmaceuticallyacceptable salts thereof. Mixtures of stereoisomers, as well as isolatedspecific stereoisomers, are also included. During the course of thesynthetic procedures used to prepare such compounds, or in usingracemization or epimerization procedures known to those skilled in theart, the products of such procedures can be a mixture of stereoisomers.

Compounds described herein comprise atoms in both their natural isotopicabundance and in non-natural abundance. The disclosed compounds can beisotopically-labelled or isotopically-substituted compounds identical tothose described, but for the fact that one or more atoms are replaced byan atom having an atomic mass or mass number different from the atomicmass or mass number typically found in nature. Examples of isotopes thatcan be incorporated into compounds of the invention include isotopes ofhydrogen, carbon, nitrogen, oxygen, phosphorous, fluorine and chlorine,such as 2 H, 3 H, 13 C, 14 C, 15 N, 18 O, 17 O, 35 S, 18F and 36 Cl,respectively. Compounds further comprise prodrugs thereof, andpharmaceutically acceptable salts of said compounds which contain theaforementioned isotopes and/or other isotopes of other atoms are withinthe scope of this invention. Certain isotopically-labelled compounds ofthe present invention, for example those into which radioactive isotopessuch as 3 H and 14 C are incorporated, are useful in drug and/orsubstrate tissue distribution assays. Tritiated, i.e., 3 H, andcarbon-14, i.e., 14 C, isotopes are particularly preferred for theirease of preparation and detectability. Further, substitution withheavier isotopes such as deuterium, i.e., 2 H, can afford certaintherapeutic advantages resulting from greater metabolic stability, forexample increased in vivo half-life or reduced dosage requirements and,hence, may be preferred in some circumstances. Isotopically labelledcompounds of the present invention and prodrugs thereof can generally beprepared by carrying out the procedures below, by substituting a readilyavailable isotopically labelled reagent for a non-isotopically labeledreagent.

The compounds described in the invention can be present as a solvate. Insome cases, the solvent used to prepare the solvate is an aqueoussolution, and the solvate is then often referred to as a hydrate. Thecompounds can be present as a hydrate, which can be obtained, forexample, by crystallization from a solvent or from aqueous solution. Inthis connection, one, two, three or any arbitrary number of solvate orwater molecules can combine with the compounds according to theinvention to form solvates and hydrates. Unless stated to the contrary,the invention includes all such possible solvates.

It is also appreciated that certain compounds described herein can bepresent as an equilibrium of tautomers. For example, ketones with anα-hydrogen can exist in an equilibrium of the keto form and the enolform.

Likewise, amides with an N-hydrogen can exist in an equilibrium of theamide form and the imidic acid form. Unless stated to the contrary, theinvention includes all such possible tautomers.

It is known that chemical substances form solids which are present indifferent states of order which are termed polymorphic forms ormodifications. The different modifications of a polymorphic substancecan differ greatly in their physical properties. The compounds accordingto the invention can be present in different polymorphic forms, with itbeing possible for particular modifications to be metastable. Unlessstated to the contrary, the invention includes all such possiblepolymorphic forms.

Compounds of the Invention

Preferred MTKI's of the present invention are characterized by an IC50concentration threshold for 50% activity of less than 10 nanomolar(“nM”). Preferred MTKI's of the present invention include thosecompounds in Table 1.

TABLE 1 Preferred MTKI's of the present invention MTKI/IC50 for VEGFR2Structure Cabozantinib 0.035 nM

Axitinib 0.200 nM

Cediranib 0.500 nM

Ponatinib 1.500 nM

Foretinib 2.800 nM

MGCD-265 3.000 nM

Motesanib 3.000 nM

Regorafenib 4.200 nM

Tivozanib 6.500 nM

Sunitinib 9.000 nM

In another preferred embodiment, preferred moieties include optionallysubstituted C2 to C25 alkyl groups bound to a peptide or a protein.

In a representative embodiment, cabozantinib derivatives include thoseof formula (I):

wherein R¹, R², R³, R⁴ and R⁵ are each individually selected fromabsent, hydrogen, oxygen, carbon, potassium, sulfur, phosphorus,nitrogen, —O—CH₃, a carbonyl, a sulfhydryl, a phosphatyl, an amide, anamine, a quaternary amine, a phosphate, a phosphonate, a sulfate, asulfonate, a carboxylate, a urethane, and an optionally substituted C2to C25 alkyl group optionally bound to a peptide or a protein and atleast one of R¹, R², R³ R⁴ and R⁵ is not absent, hydrogen, oxygen,carbon, potassium, sulfur, phosphorus, nitrogen, —O—C, a carbonyl, asulfhydryl, a phosphatyl, an amide, an amine, a quaternary amine, aphosphate, a phosphonate, a sulfate, a sulfonate, a carboxylate, or aurethane.

In a more preferred embodiment the optionally substituted C2 to C25alkyl group is substituted with one or more substituents selected fromthe group consisting of an optionally substituted carbonyl, sulfhydryl,phosphate, phosphatyl, phosphonate, amide, amine, quaternary amine,sulfate, sulfonate and carboxylate.

In another more preferred embodiment, the one or more substituents areoptionally substituted with a fatty acid or a second alkyl, preferablypalmitate.

Representative compounds of formula (I) or (III) include:

wherein X is a peptide, a protein or absent.

Further, representative compounds of formula (I) include those in Table2 below.

TABLE 2 Representative Cabozantinib Derivatives Name and EstimatedDerivative Log P Value

Cabozantinib N-acyl methyl palmitate Estimated log P of 6.77

Cabozantinib N-acyl methyl oleate Estimated log P of 6.28

Cabozantinib sulfate

Cabozantinib phosphodipalmitate

Cabozantinib palmitate

Cabozantinib palmitate

(Compound 4).Compositions of the Invention

The selection of MTKI derivatives for slow and/or delayed conversion canbe enhanced by selection of compositions to aid in slow and/or delayedrelease, such as nanosuspensions or nanoencapsulation. Fornanosuspensions, methods well known to experts in the art such asmilling or formulation via supercritical solutions may be used.Preferred nanosuspensions have particle size of less than 400 nM,preferably less than 150 nM and more preferably between 50 and 100 nM.For saline nanosuspensions, less than 1 mg/ml of a compound of thepresent invention is formulated with a particle size from about 50 toabout 300 nM. Preferred nanoencapsulation is achieved through the use ofa caprylactone polymer, though poly(D,L-lactide-co-glycolide) (“PLGA”)and PLGA-alpha tocopherol or other encapsulation polymers may be used.Preferred emulsions allow for substantially greater than 1% oil to becombined with the water phase. For example, a 50:50 oil in water ratiois sufficient for intravitreal drug delivery. Double emulsions of thepresent invention include, but are not limited to, oil-in-water-in-waterand water-in-oil-in-water double emulsions.

Compositions of the present invention also include the use ofnanoparticles, microparticles, nanocapsules, microcapsules, nanospheresand microspheres. Processes for preparing nanoparticles and doubleemulsions are detailed in Song K. C., et al., The effect of type oforganic phase solvents on particle size ofpoly(D,L-lactide-co-glycolide) nanoparticles, Colloids Surf A PhsyiochemEng Aspects, 2006, 276, 162-167, and in U.S. Patent ApplicationPublication No. 2013/0209566, each of which are incorporated byreference in its entirety. Processes for preparing microspheres aredetailed in Alhenn D. et al., Microsphere preparation using the nontoxicsolvent glycofurol, Pharm Res, 2011, March, 28 (3), 563-571, which isincorporated by reference in its entirety. Processes for preparing anoil-in-water emulsion are detailed in Daull et al., A preliminaryevaluation of dexamethasone palmitate emulsion: a novel intravitrealsustained delivery of corticosteroid for treatment of macular edema, JOcul Pharmacol Ther, 2013 March, 29(2), 258-269, which is incorporatedby reference in its entirety.

Compositions of the present invention may be formulated as emulsions ormicroemulsions. Processes for preparing emulsions and microemulsions arewell known in the art and include commercial lipoemulsions such asIntralipid® (Intralipid is a registered trademark of Fresenius Kabi AB),Abbolipid and SolEmuls® as described in Muller R H, et al.,SolEmuls-novel technology for the formulation of i.v. emulsions withpoorly soluble drugs, Int J Pharm, 2004 Jan. 28, 269(2), 293-302.

Compositions of the present invention include excipients not limited toantioxidants, surfactants, viscosity enhancers, tonicity adjustors,osmolality modifiers, solubility enhancers, preservatives and buffers.

Antioxidants suitable for the present invention include, but are notlimited to, alpha tocopherol, sodium metabisulfite, sodium thiosulfate,acetylcysteine, butylated hydroxyanisole and butylated hydroxytoluene.

Surfactants suitable for the present invention include, but are notlimited to, nonionic, cationic and/or anionic surfactants. Specificsurfactants include cyclodextrins, polyoxyl alkyls, poloxamers orcombinations thereof. Preferred nonionic surfactants include tyloxapol,alpha cyclodextrin, beta cyclodextrin, gamma cyclodextrin, a poloxamer,a polysorbate and a polyoxyl stearate Further, substitution of othersurfactants compatible with ophthalmic use allows for similarcomposition advantages, which may included but is not limited to one ormore of a nonionizing surfactant such as poloxamer, Poloxamer 188,Poloxamer 407, Polysorbate 20, Polysorbate 80, ionically charged (e.g.anionic) beta-cyclodextrins with or without a butyrated salt (Captisol®;(sulfobutylether β-cyclodextrin, Captisol is a registered trademark ofCydex Pharmaceuticals), 2-hydroxypropyl beta cyclodextrin (“HPβCD”),Polyoxyl 35 stearate, Polyoxyl 40 castor oil and Polyoxyl 40hydrogenated castor oil, poloxamer 103, poloxamer 123, and poloxamer124, poloxamer 407, poloxamer 188, and poloxamer 338, any poloxameranalogue or derivative, polysorbate, polysorbate 20, polysorbate 40,polysorbate 60, polysorbate 80, any polysorbate analogue or derivative,cyclodextrin, hydroxypropyl-β-cyclodextrin,hydroxypropyl-γ-cyclodextrin, randomly methylated β-cyclodextrin,β-cyclodextrin sulfobutyl ether, γ-cyclodextrin sulfobutyl ether orglucosyl-β-cyclodextrin, any cyclodextrin analogue or derivative,polyoxyethylene, polyoxypropylene glycol, an polysorbate analogue orderivative, polyoxyethylene hydrogenated castor oil 60, polyoxyethylene(200), polyoxypropylene glycol (70), polyoxyethylene hydrogenated castoroil, polyoxyethylene hydrogenated castor oil 60, polyoxyl, polyoxylstearate, nonoxynol, octyphenol ethoxylates, nonyl phenol ethoxylates,capryols, lauroglycol, PEG such as PEG400, Brij®35(polyoxyethyleneglycol dodecyl ether; Brij is a registered trademarkof Uniqema Americas LLC), glyceryl laurate, lauryl glucoside, decylglucoside, or cetyl alcohol; or zwitterion surfactants such as palmitoylcarnitine, cocamide DEA, cocamide DEA derivatives cocamidopropylbetaine, or trimethyl glycine betaine, N-2(2-acetamido)-2-aminoethanesulfonic acid (ACES), N-2-acetamido iminodiacetic acid (ADA),N,N-bis(2-hydroxyethyl)-2-aminoethane sulfonic acid (BES),2-[Bis-(2-hydroxyethyl)-amino]-2-hydroxymethyl-propane-1,3-diol(Bis-Tris), 3-cyclohexylamino-1-propane sulfonic acid (CAPS),2-cyclohexylamino-1-ethane sulfonic acid (CHES),N,N-bis(2-hydroxyethyl)-3-amino-2-hydroxypropane sulfonic acid (DIPSO),4-(2-hydroxyethyl)-1-piperazine propane sulfonic acid (EPPS),N-2-hydroxyethylpiperazine-N′-2-ethane sulfonic acid (HEPES),2-(N-morpholino)-ethane sulfonic acid (IVIES), 4-(N-morpholino)-butanesulfonic acid (MOBS), 2-(N-morpholino)-propane sulfonic acid (MOPS),3-morpholino-2-hydroxypropanesulfonic acid (MOPSO),1,4-piperazine-bis-(ethane sulfonic acid) (PIPES),piperazine-N,N′-bis(2-hydroxypropane sulfonic acid) (POPSO),N-tris(hydroxymethyl)methyl-2-aminopropane sulfonic acid (TAPS),N-[tris(hydroxymethyl)methyl]-3-amino-2-hydroxypropane sulfonic acid(TAPSO), N-tris(hydroxymethyl) methyl-2-aminoethane sulfonic acid (TES),2-Amino-2-hydroxymethyl-propane-1,3-diol (Tris), tyloxapol, Span® 20-80(sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate,and sorbitan monooleate; Span is a registered trademark of UniqemaAmericas Inc.), Tween® 20 (Tween is a registered trademark of UniqemaAmericas LLC), Tween® 80, Labrasol® (caprylocaproyl macrogol-8glycerides; Labrasol is a registered trademark of Gattefosse SAS).Surfactants of the present invention can be at a concentration fromabout 0.01% to about 99% w/v, preferably from about 1% to about 30% w/v.

Solubility enhancers (i.e. solvents) suitable for the present inventioninclude, but are not limited to, glycofurol (a.k.a. tetraglycol andtetraethylene glycol), dimethyl sulfoxide (“DMSO”), vitamin E TPGS(d-alpha tocopherol polyethylene glycol 1000 succinate), dimethylsorbide (“DMI”), ethyl acetate, acetonitrile, ethyl alcohol, alcohols,polyols, amides, esters, polyethylene glycol, propylene glycol,propylene glycol ethers, polysorbates, poloxamers, cyclodextrins, Span®20-80, dimethyl isosorbide, isopropyl myristate oil and complexingagents such as cyclodextrins and nicotinamide or a combination thereof.Solubility enhancers of the present invention can be at a concentrationfrom about 0.01% to about 99% w/v, preferably from about 1% to about 30%w/v.

Viscosity enhancers suitable for the present invention include, but arenot limited to, carboxymethyl cellulose (“CMC”), methylcellulose, methylcellulose 4000, hydroxymethyl cellulose, hydroxypropyl cellulose,hydroxypropylmethyl cellulose, hydroxyl propyl methyl cellulose 2906,carboxypropylmethyl cellulose, hydroxyethyl cellulose, or hydroxyethylcellulose, hyaluronic acid, dextran, polyethylene glycol, polyvinylalcohol, polyvinyl pyrrolidone, gellan, carrageenan, alignic acid,carboxyvinyl polymer or combinations thereof. Viscosity enhancers of thepresent invention can be at a concentration from about 0.01% to about99% w/v, preferably from about 0.1% to about 10% w/v.

A tonicity adjustor can be, without limitation, a salt such as sodiumchloride (“NaCl”), potassium chloride, mannitol or glycerin, or anotherpharmaceutically or ophthalmically acceptable tonicity adjustor.Tonicity adjustors of the present invention can be at a concentrationfrom about 0.01% to about 99% w/v, preferably from about 0.1% to about10% w/v.

Osmolality modifiers suitable for the present invention include, but arenot limited to, mannitol, sorbitol, glycerol and a combination thereof.Osmolality modifiers of the present invention can be at a concentrationfrom about 0.01% to about 99% w/v, preferably from about 0.1% to about10% w/v.

Preservatives that can be used with the present invention include, butare not limited to, benzalkonium chloride (BAK), chlorobutanol,thimerosal, phenylmercuric acetate, disodium ethylenediaminetetraaceticacid, phenylmercuric nitrate, perborate or benzyl alcohol. In apreferred embodiment the preservative is BAK at a concentration of about0.001% to about 1.0% w/v, more preferably at a concentration of about0.02% w/v.

Various buffers and means for adjusting pH can be used to prepareophthalmological compositions of the invention. Such buffers include,but are not limited to, acetate buffers, citrate buffers, citric acidbuffers, phosphate buffers and borate buffers. It is understood thatacids or bases can be used to adjust the pH of the composition asneeded, preferably of 1 to 10 mM concentration, and more preferablyabout 5 mM. In a preferred embodiment the pH is from about 3.0 to about8.0, in a more preferred embodiment the pH is from about 7.0 to about7.5.

In another embodiment, compositions of the present invention comprisepolylactide polymers. Polylactide polymers suitable for the presentinvention include, but are not limited to, polylactic acid,poly-L-lactide, poly-D-lactide, poly(D,L-lactide)poly(L-lactide-co-D,L-lactide) and poly (D,L-lactide-co-glycolide).

Diseases to be Treated with Compounds, Compositions and Methods of theInvention

Diseases that may be treated by compositions and methods of the presentinvention include ophthalmic conditions, but are not limited to:

A) Maculopathies/Retinal degenerations including non-exudative (dry)age-related macular degeneration (“AMD”), prophylactic treatment ofsevere dry AMD to prevent onset of wet AMD, exudative (wet) AMD,choroidal neovascularization, diabetic retinopathy, particularlyprophylactically in the treatment of background diabetic retinopathy toprevent diabetic macular edema and or proliferative retinopathy, thetreatment prophylactically of proliferative retinopathy to preventvitreous hemorrhage, and particularly preferentially in the presence ofproliferative retinopathy where conventional treatments (antibodyanti-VEGF) may induce increased fibrovascular change with contractionalong the retina and possible retinal detachment, acute macularneuroretinopathy, central serous chorioretinopathy, cystoids macularedema and macular edema;

B) Uveitis/Retinitis/Choroiditis including acute multifocal placoidpigment epitheliopathy, Behcet's disease, Birdshot retinochoroidopathy,infectious (syphilis, lime, tuberculosis, toxoplasmosis), intermediateuveitis (pars planitis), multifocal choroiditis, multiple evanescentwhite dot syndrome, ocular sarcoidosis, posterior scleritis, serpiginouschoroiditis, subretinal fibrosis, uveitis syndrome, andVogt-Koyanagi-Harada syndrome;

C) Vascular diseases/Exudative diseases including Coat's disease,parafoveal telangiectasis, papillophlebitis, frosted branch angitis,sickle cell retinopathy, other hemoglobinopathies, angioid streaks andfamilial exudative vitreoretinopathy;

D) Traumatic/surgical diseases including sympathetic ophthalmia, uveiticretinal disease, retinal detachment, trauma from laser photocoagulationor photodynamic therapy, hypoperfusion during surgery, radiationretinotherapy and bone marrow transplant retinopathy;

E) Proliferative disorders including proliferative vitrealretinotherapy, epiretinal membranes, proliferative diabetic retinopathyand retinopathy of prematurity (retrolental fibroplastic);

F) Infectious disorders including ocular histoplasmosis, oculartoxocariasis, presumed ocular histoplasmosis syndrome, endophthalmitis,toxoplasmosis, retinal diseases associated with HIV infection, choroidaldisease associated with HIV infection, uveitic disease associated withHIV infection, viral retinitis, acute retinal necrosis, progressiveouter retinal necrosis, fungal retinal diseases, ocular syphilis, oculartuberculosis, diffuse unilateral subacute neuroretinitis and myiasis;

G) Genetic disorders including systemic disorders with associatedretinal dystrophies, congenital stationary night blindness, conedystrophies, fundus flavimaculatus, Best's disease, Pattern dystrophy ofthe retinal pigmented epithelium, X-linked retinoschisis, Sorsby'sfundus dystrophy, benign concentric maculopathy, Bietti's crystallinedystrophy, psuedoxanthoma elasticum and Osler Weber syndrome;

H) Retinal tears/holes including retinal detachment, macular hole andgiant retinal tear;

I) Tumors including retinal disease associated with tumors, solidtumors, tumor metastasis, benign tumors (e.g. hemangiomas,neurofibromas, trachomas, pyogenic granulomas), congenital hypertrophyof the retinal pigmented epithelium, posterior uveal melanoma, choroidalhemangioma, choroidal osteoma, choroidal metastasis, combined hamartomaof the retina and retinal pigmented epithelium, retinoblastoma,vasoproliferative tumors of the ocular fundus, retinal astrocytoma andintraocular lymphoid tumors;

J) Neovascular ischemia including neovascular glaucoma, anterior segmentischemia syndromes, corneal neovascularization including post cornealsurgery such as post penetrating keratoplasty, herpetic keratitis andother ischemic or corneal inflammatory conditions; and

K) Other diseases that may be treated by compositions and methods of thepresent invention include cancers not limited to chronic myeloidleukemia (“CML”), acute lymphocytic leukemia, non-small cell lungcancer, pancreatic cancer, gastrointestinal stromal tumors,hypereosinophilic syndrome, systemic mastocytosis, breast cancer withHER2/neu overexpression, chronic phase or accelerated Ph-positive CML,renal cell cancer, and hepatocellular carcinoma.

In one embodiment, the present invention is directed to oraladministration of a compound of the present invention to a subject inneed thereof.

In another embodiment, the present invention is directed to intravenousinjection of a compound of the present invention to a subject in needthereof.

Diabetic retinopathy in particular may be therapeutically improved orworsened by conventional anti-VEGF therapies (antibody ant-VEGFincluding Lucentis®, Eylea®), where background retinopathy leading tomacular edema may be improved. With the onset of proliferativeretinopathy however conventional anti-VEGF therapy causes increasedfibrosis. Van Geest R. J. et al., A shift in the balance of vascularendothelial growth factor and connective tissue growth factor bybevacizumab causes the angiofibrotic switch in proliferative diabeticretinopathy Br J Ophthalmol, 2012 April, 96(4), 587-90. It is asurprising and previously unrecognized virtual discovery thatintravitreal injection of preferred embodiments cabozantinib N-acylmethyl palmitate and foretinib N-acyl methyl palmitate suppressintraocular proliferative retinopathy, and most particularly diabeticproliferative retinopathy. The suppression of intraocular proliferativeretinopathy in turn suppresses fibrotic induction and the most severemanifestations of proliferative eye disease. This suppression also isvirtually discovered to occur when the methyl of the preferredembodiments is replaced by any alkyl group. It is of not that N-acylmethyl palmitate and foretinib N-acyl methyl palmitate, without orwithout substitution of the methyl group are virtually discovered tosuppress VEGFR and c-MET. Proliferative retinopathy progression tofibrovascular proliferation has extremely high morbidity with changesincluding but not limited to fibrovascular traction, vitreofibrosis,macular pucker and related distortion, epiretinal membranes with inducedretinal shear, retinal detachment, increased morbidity with intravitrealinjection and poor prognosis after vitrectomy with or without dissectionof epiretinal membranes and separation and treatment of fibrovascularmembranes. As diabetic macular edema is amenable to anti-VEGF therapy,its use in patients with preproliferative severe peripheral ischemicdisease, and or patients with early proliferative disease may enhancethe onset of fibrovascular proliferative morbidity, whereas the presentinvention using MTKIs combining VEGF suppression with c-MET suppressionmay both reduce diabetic macular edema and suppress diabeticfibrovascular proliferation.

The following Examples are provided solely for illustrative purposes andare not meant to limit the invention in any way.

EXAMPLES Example 1 Synthesis of Cabozantinib N-acyl Methyl Palmitate

Method

Cabozantinib was incubated with bromomethyl palmitate in the presence oftetraphenylborate (“NaBPh₄”), acetonitrile (“CH₃CN”) at 82° C. for Xhours resulting in cabozantinib N-acyl methyl palmitatetetraphenylborate. The cabozantinib N-acyl methyl palmitatetetraphenylborate is then incubated with Dowex®-1-chloride (Dowex is aregistered trademark of Dow Chemical Company) and acetonitrile:isopropylalcohol (iPA) to yield cabozantinib N-acyl methyl palmitate chloride.

Example 2 (Virtual)

Formulation

Cabozantinib N-acyl methyl palmitate (CNAMP) was formulated forintravitreal injection using isopropyl myristate or oleic acid combinedwith about 10% w/v cyclodextrin and from about 10% to about 30% w/vD-alpha tocopherol PEG 1000 succinate (“TGPS”) which were thensolubilized via well-known oil solubilization techniques to create afirst solution. The first solution was then added to a saturated fattyacid (e.g. octanoic acid) combined with lecithin or lecithin derivatives(e.g. phosphatidyl choline), a glycerol fatty acid ester (e.g. propyleneglycol fatty acid esters such as polyoxyethyleneglyceroltriricinoleate), a sorbitan fatty acid ester (e.g. Span® 20, Span® 80)or a olyoxylethylene sorbitan fatty acid ester (e.g. Tween® 20, Tween®80), and optionally a co-surfactant (e.g. propylene glycol, glycerol,PEG 400, 1,2-propanediol), which were then solubilized as amicroemulsion using commercial lipoemulsion techniques (e.g.Intralipid®, Abbolipid).

Method

50 uL of an oil or emulsion containing about 10 mg/mL to 20 mg/mL ofcabozantinib N-acyl methyl palmitate was administered via midvitrealinjection into one eye of a mammal (preferably a pigmented rabbit or aprimate). 50 uL of either Lucentis® or Eylea® was administered into theremaining eye of the mammal.

2 weeks after administration a subretinal choroidal neovascularization(CNV) was caused in the eyes of the mammal using techniques explained inQui G et al., A new model of experimental subretinal neovascularizationin the rabbit, Exp Eye Res, 2006 July, 83(1), 141-152. 6 weeks aftersubretinal CNV eyes of the mammal were sacrificed for examination.

Results

Greater suppression of fibrovascular proliferation will be found in theeye with intravitreal injection of cabozantinib N-acyl methyl palmitate.In addition, a long-lasting suppression of macular edema will be found.

Example 3. In-Vitro Kinase Inhibition Assay

Method

Compounds 2-4 and cabozantinib were each tested for binding of c-Met,VEGFR2, TIE2 and the control compound, staurosporine. Specifically, eachcompound was tested at a 3-fold serial dilution starting at 10microMolar (“μM”) in a 10-dose IC50 mode into an enzyme/substratemixture using acoustic technology, and pre-incubated for 20 minutes toensure compounds were equilibrated and bound to the enzyme.Staurosporine was used as a control and was tested at a 4-fold serialdilution starting at 20 μM. Next, 5 concentrations of ATP were added toinitiate the reaction. The activity was monitored every 5-15 min for atime course study.

TABLE 3 IC50 Data for Compound 2 on Various Kinases Compound IC50* (M):Kinase [ATP](μM): Staurosporine Cabozantinib Compound 2 c-Met 102.16E−07   5.08E−10 3.76E−06 VEGFR2 20 1.86E−08 <5.08E−10 TIE2 301.20E−07   4.90E−07 *Empty cells indicate no inhibition or compoundactivity that could not be fit to an IC50 curve for any of the 3kinases.Results

As can be seen in Table 3, Compound 2 provided significant inhibition ofc-Met. Compounds 3 and 4 either demonstrated no inhibition or theiractivity that could not be fit to an IC50 curve for any of the 3kinases.

What is claimed is:
 1. A compound selected from

wherein X is a peptide, a protein or absent.
 2. A composition comprisinga compound of claim 1 and one or more pharmaceutically acceptableexcipients.